Variable condenser



S. COHEN VARIABLE CONDENSER May 3o, 1933..

Filed Aug. 15, 1931 2 Sheets-Sheet 2 JNVENToR. 61" 5am/wwf @of/zw,

BY W e, ATTORNEY Patented May 30, 1933 UNITED STA TEs PATENT OFFICE.SAMUEL COHEN, OF BROOKLYN, NEW YORK, AS\SIGNOR TO GENERAL INSTRUHENTCORPORATION, OF NEW YORK, N. Y., .AI CORPORATION OF NEW YORK 'VARIBLEcoNDENsER Application led August 13, 1931. Serial No. 556,888.

My invention relates broadly to electrical condensers and moreparticularly to the construction of multiple variable electricalcondensers having meansfor compactly I mounting a compensating ortrimmer condenser adjacent each of the sets of rotor and stator platesin the multiple variable condenser.

One of the objects of my invention is toy pensating condenser individualto each of' the Avariable capacity units constituting the multiplevariable condenser;

Still another object of my invention is to provide a compactconstruction of multiple variable condenser including 'a chassisarranged to support a multiplicity of variable 80 condenser units, theside walls of the chassis having a portion thereof offset one fromaliother for providing mounting means for a compensating condenseradjacent each of the variable condenser units, the compensating aicondensers being so mounted that the parts thereof areentirely shieldedby laterally extending electrostatic shields forming part of t econdenser chassis.

A further object -of-my invention is to l4:0 provide a construction ofmultiple variable condenser, having a chassis with opposite side wallswherein diametrically oppositev apertures are"A arranged in the sidewalls and integrally connected tongues projected upwardly from thebottom of the chassis into -a planeparallel with the plane of the sidewalls but offset therefrom for a distance ich lies withinthe lane o thesi e walls 5 and forms an insulate suspension means for the stator plateunits and for the compensating condenser units.

Other and further objects of ymy invention reside in the compactconstruction of a multiple variable condenser-as set forth vmore e fullyin the specification hereinafter following by reference to theaccompanying drawings;- in which:

Figure 1 is a side elevation of the multiple variable condenserstructure of my inven- .Q0 tion; Fig. 2 is a plan view showing thearrangement of parts of the multiple variable condenser shown in Fi 1;Fig. 3 is another side elevation of t e multiple variable condensertakenfrom a position opposite to that at which the view 1n Fig. 1 is taken;Fig. 4 is allateral cross-sectional view taken through the condenser online 4--4 of Fig.

2; and. Fig. 5` -is a fragmentary sectional view taken through thecondenser lon line 5--5 of Fig. l. f

Referring to the drawings in detail, the condenser chassis is indicatedat 5 havingl a bottom portion and upstanding side wall e portions. Thereare a plurality of plate-: members extending laterally of the condenserchassis such as represented by reference characters 1, 2, 3 and 4..Plates 1 vand 4 constitute end plates for the condenser chassis whileplates 2 and 3 constitute elec-- trostatic shields disposed'intermediatethe sets of rotor andstator plates constituting each of the variablecondenser units. A rotatable shaft 6 extends through the electrostaticshields 2 and 3 and is journled in the v end plates 1 and 4, thejournals being represented similarly at la and 4a in the end plates 1and 4, respectively. The rotatable shaft 64 carries sleeve members 7, 8and 9 which are grooved to support `sets of rotor plates represented at20, 21 and 22. The sets of rotorplates are aligned t0 be interleavedwith the sets of stator plates 10, 11 and 12. IThe stator plates arearranged-laterally of the chassis and supported by means at each sidethereof in the form of sets of insulated vpanel members 23, 24 and 5 25,as shown. The side walls ofthe con denser chassis are represented at and5b.

The-se `side twalls are provided with dia- 10' metrically oppositeapertures 50 therein. These apertures are partially closed by anupstanding tongue 5d which is bent fromk ldistance equal to thethickness of the side wall. The tongue 5d serves as a carrier for theassociated insulated panel member.

As shown in Fig.l 4 the. insulated panel 23 is riveted at v23a to theupstanding portion of 5d. The panel 33 projects upwardly andsubstantially fills the space provided by the aperture 5c in the sidewall of the condenser chassis. The insulated panel 23 is aperturedadjacent the to thereof for the passage of screws 26 which pass throughthe insulated panel and through the chalinel shaped member 27 and aresecured in position by means of nuts 28. The channel shaped member 27thereon has diametrically opposite supports for the edges of the sets ofstator plates 10, 11 and 12, arranged in such position that the rotorlates may be interleaved therewith. yIn or ery to provide for connectionto the sets of stator plates, lugs 26a: may be secured under the headsof screws 26 at one side of the condenser chassis. At the other side ofthe condenser chassis I provide a mounting for the compensatingcondenser for each condenser unit. Thek compensating condenser isconstituted by a plate member 29 throu h which screws 26 lpass formechanical y mounting the plate member 29 and estab-y lishing electricalconnection between plate member 29v and the sets of stator plates. Theplate member 29 has a ca acity area at ,the upper portion thereof w ichlies immediately adjacent the upper portion of the side wall 5b. Anaperture is provided in the upper portion ofiplate 29 for the passage ofan adjusting screw 30 which enters the side wall 5b and is adjustableagainst plate 29 for varying the spacial relation between plate 29 andthe side wall 5b. A dielectric sheet as shown at 31 extends between theplate 29 andthe side wall 5b and is supported by laterally projectingtongues 29a on plate 29 as well as by means of adjusting screw 30. Plate29 has sufficient resiliency to normall tend to force plate 29 away fromthe side wall of the condenser. However by turning adjusting screw 30thei creasing the ca aeity of the compensating condenser. Adjustment ofthe compensatingcondenser permits the maximum to minimum capacity ratioof each condenser section to be fixed thereby' enabling the condenser tobe efiiciently matched with the tuning circuit inwhich it is employed inan adjustably tuned amplifier system. Electrical connection isestablished with plate .29 of the compensating condenser and with the-associated stator plates with the projecting lug 29?), arranged asillustrated. The fact that plate 29 is directly connected with thestator plates, places the compensatingcondenser effectively in shuntwith each condenser unitl inasmuch as the sets of rotor plates areconnected to the condenser frame of which the side 5b-is an integralpart.

It will be observed that the insulated panel members are so supported bythe upstanding tongues 5b that they lie in the plane of the side wall ofthe condenser chassis. This arrangement is possible because of thearrangement of the tongues 5d which have their exterior surfacesextending in a plane coincident with the plane of the interiorsurfacesvof the side walls of the. condenser chassis. The insulated panel memberhas a thickness substantially equal to the thickness of'the wall of thecondenser chassis and so occupies a space substantially within thelimits of the thickest dimensions of the side walls. The mounting of thecompensating condenser is in this way arrangedfso compactly that allparts of the compensating, condenser lie between the adjacentelectrostatic shields'and closely conform with the lateral dimensions ofthe condenser. This facilitates quantity production of condensers inmanufacture and simplifies assembly, installation and wirin of thecondenser in circuit with the amplifier system.

While I have described my invention in i one of its preferredembodiments I desire that it be understood that modifications may bemade and that no limitations upon my invention are intended other thanare imposed bythe' scope of the appended claims.

What I claim as new and desire to secure by Letters Patent in the UnitedStates is as follows:

1. Ina multiple variable condenser, a condenser chassis having a bottomportion and .upstanding side wall portions, said side wall portionsbeing apertured in diametrically opposite positions, tongues integrallyconnected with the bottom of said chassis extending vertically therefromin a plane inwardly offset fromvthe plane of the side wall of saidchassis for a distance equal to the thickness of the sidewall portionsof spacial relation between plate 29 and thellaterally of said chassis,insulated means side wall 5b may be decreased thereby insupportedv byopposite tongues and conf/wal nected with opposite ends of said statorplates and extending in the plane of the side wall portions of saidchassis for suspend- -ing said stator plates laterally of said chassis,anda trimmer condenser plate carried by said insulated means in coactingrelation to the side wall'of said chassisl 2. In a multiple variablecondenser, a condenser chassis having a bottom portion and l0 upstandingside wall portions, said side wall portions being apertured indiametrically l opposite positions,ytongues .integrally connected withthe bottom of said chassis extending vertically therefrom," said tonguesbeing disposed in a plane parallel to the plane of said side walls butinside the limits of said'side walls with the outside face of saidtongues dis osed in a plane coinciding with the plane o the inside faceof said side Wall portions, an insulated plate connected with each ofsaid tongues and extending vertically in a position filling theapertures in said sidewalls, sets of stator plates suspended betweenopposite insulated lates in a position adapted to be interleave by setsof rotor plates adjustably mounted with respect thereto, and a trimmercondenser p ate carried by said insulated means in coaoting relation tothe side Wall of said chassis.

3. In a multiple variable condenser comprising, a condenser chassis andincluding a bottom portion and a pair of opposite side wall portions,the side wall portions being apertured .at opposite positions, tonguesintegrally connected with said bottom portion and extending verticallyupwardly therefrom to a position within the apertures in said sidewalls, the exterior surface of said 40 tongues extending in a planecoincident with the lane of the interior surface of the side lp of saidcondenser chassis, an insulated plate attached at its lower end to eachof said tongues, laterally extending sets of stator plates within saidcondenser chassis and connections, ybetween opposite ends of said statorplates andthe upper portions of said insulated plates for suspendingsaid stator plates, a compensating condenser having an adjustable platesupported by each i of said insulated lates and coacting with said sidewall portions, and a rotatable shaft journaled in said condenser chassisand carr ing `a lurality of sets of rotor plates t ereon a apted to beinterleaved with said sets of stator plates. i

4. In a multiple variable condenser a condenser chassis comprising abottom portion and vertically extending sidewall portions sets of statorplates extending laterally of said chassis, a rotor shaft journaled insaid chassis sets of rotor plates carried by said rotor sliaft andadapted to be variably interleaved with said stator plates, said side 95wall portions being cut to form apertures aligned with opposite ends ofsaid stator plates and tongues integrally connected at tothe thicknessof the wall of said chassis,

and means extending through said panels for suspending the said sets ofstator plates from the opposite ends thereof, and a compensatingcondenser having an adjustable plate supported from certain of saidinsulated panels and coacting with the side wall portion of saidchassis.

In testimony whereof, I aiiix my signature.

SAMUEL COHEN.

